Feed too big, or another bug?

[Tagliaerbe]

Hi,
i've a problem very similar to this:
http://groups.google.com/group/feedburner-services/browse_thread/thread/e5a356cbb93d35dc/9c52d119a753796e

My feed is http://feedproxy.google.com/tagliaerbe (or
http://feeds2.feedburner.com/tagliaerbe, if you prefer :-)), and it
has stopped to update 3 days ago.

- FeedMedic tells me: "Error getting URL: 502 - Bad Gateway"
- Troubleshootize tells ms: "Your feed filesize is larger than 512K.
You need to reduce its size in order for FeedBurner to process it.
Tips for controlling feed file size with Blogger can be found in Tech
Tips on FeedBurner Forums, our support site."

but:

- Feed Validator tells me: "Congratulations! This is a valid RSS
feed."
- Web Sniffer tells me that the size of my feed is 77.94 KiB

Please, help me :-)

Thanks!